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Related papers: Magnetic Spiral Arms and Galactic Outflows

200 papers

The role of spiral arms in galaxies -- whether they enhance star formation efficiency or primarily act as material gatherers -- remains an open question. Observational studies have yielded ambiguous results, in part due to the choice of…

Astrophysics of Galaxies · Physics 2025-10-07 Bingqing Sun , Daniela Calzetti , Andrew J. Battisti

The exploration of mean-field galactic dynamos affected by a galactic spiral pattern, begun in Chamandy et al. (2013, hereafter Paper I) with numerical simulations, is continued here with an asymptotic solution. The mean-field dynamo model…

Astrophysics of Galaxies · Physics 2015-06-12 Luke Chamandy , Kandaswamy Subramanian , Anvar Shukurov

Studying the nature of spiral arms is essential for understanding the formation of the intricate disc structure of the Milky Way. The European Space Agency's Gaia mission has provided revolutionary observational data that have uncovered…

Astrophysics of Galaxies · Physics 2024-08-28 Natsuki Funakoshi , Noriyuki Matsunaga , Daisuke Kawata , Junichi Baba , Daisuke Taniguchi , Michiko Fujii

Radio synchrotron emission is a powerful tool to study the strength and structure of magnetic fields in galaxies. Unpolarized synchrotron emission traces isotropic turbulent fields which are strongest in spiral arms and bars (20-30 \mu G)…

Astrophysics of Galaxies · Physics 2016-01-11 Rainer Beck

Galactic spiral shocks are dominant morphological features and believed to be responsible for substructure formation within spiral arms in disk galaxies. They can also contribute a substantial amount of kinetic energy to the interstellar…

Astrophysics of Galaxies · Physics 2015-05-19 Chang-Goo Kim , Woong-Tae Kim , Eve C. Ostriker

The Local arm of the Milky Way, a short spiral feature near the Sun whose existence is known for decades, was recently observed in detail with different tracers. Many efforts have been dedicated to elaborate plausible hypotheses concerning…

Astrophysics of Galaxies · Physics 2017-07-04 Jacques R. D. Lépine , Tatiana A. Michtchenko , Douglas A. Barros , Ronaldo S. S. Vieira

In this paper we consider the viability of these non-gravitational torques to take the gas off the plane. We show that magnetically generated warps are clearly flawed because they would wrap up into a spiral in less than two or three…

Astrophysics · Physics 2009-11-13 F. J. Sanchez-Salcedo

Observations of dwarf galaxies suggest the presence of large-scale magnetic fields. However the size and slow rotation of these galaxies appear insufficient to support a mean-field dynamo action to excite such fields. Here we suggest a new…

Astrophysics of Galaxies · Physics 2017-02-08 David Moss , Dmitri Sokoloff

With the use of a background Milky-Way-like potential model, we performed stellar orbital and magnetohydrodynamic (MHD) simulations. As a first experiment, we studied the gaseous response to a bisymmetric spiral arm potential: the widely…

Astrophysics of Galaxies · Physics 2015-05-21 Angeles Pérez-Villegas , Gilberto C. Gómez , Bárbara Pichardo

Radio continuum observations allow to reveal the magnetic field structure in the disk and halo of nearby spiral galaxies, their magnetic field strength and vertical scale heights. The spiral galaxies studied so far show a similar magnetic…

Astrophysics of Galaxies · Physics 2014-01-08 Marita Krause

Most star formation in the local Universe occurs in spiral galaxies, but their origin remains an unanswered question. Various theories have been proposed to explain the development of spiral arms, each predicting different spatial…

Large-scale magnetic fields in galaxies are thought to be generated by a turbulent dynamo. However the same turbulence also leads to a small-scale dynamo which generates magnetic noise at a more rapid rate. The efficiency of the large-scale…

Astrophysics · Physics 2020-11-25 K. Subramanian

We report the highest-fidelity observations of the spiral galaxy M51 in CO emission, revealing the evolution of giant molecular clouds (GMCs) vis-a-vis the large-scale galactic structure and dynamics. The most massive GMCs (so-called GMAs)…

The formation and evolution of galactic spiral arms is not yet clearly understood despite many analytic and numerical work. Recently, a new idea has been proposed that local density enhancements (waklets) arising in the galactic disk…

Astrophysics of Galaxies · Physics 2016-05-25 Jun Kumamoto , Masafumi Noguchi

Spiral shocks are potentially a major source of turbulence in the interstellar medium. To address this problem quantitatively, we use numerical simulations to investigate gas flow across spiral arms in vertically stratified,…

Astrophysics · Physics 2011-02-11 Chang-Goo Kim , Woong-Tae Kim , Eve C. Ostriker

In this and in a previous paper (Romero-Gomez et al. 2006) we propose a theory to explain the formation of both spirals and rings in barred galaxies using a common dynamical framework. It is based on the orbital motion driven by the…

Astrophysics · Physics 2009-11-13 M. Romero-Gomez , E. Athanassoula , J. J. Masdemont , C. Garcia-Gomez

Spiral arms shown by different components may not be spatially coincident, which can constrain formation mechanisms of spiral structure in a galaxy. We reassess the spiral arm tangency directions in the Milky Way through identifying the…

Astrophysics of Galaxies · Physics 2015-09-30 L. G. Hou , J. L. Han

We propose a theory to explain the formation of both spirals and rings in barred galaxies using a common dynamical framework. It is based on the orbital motion driven by the unstable equilibrium points of the rotating bar potential. Thus,…

Astrophysics · Physics 2016-11-23 M. Romero-Gomez

We investigate the short-term dynamical evolution of stellar grand-design spiral arms in barred spiral galaxies using a three-dimensional (3D) $N$-body/hydrodynamic simulation. Similar to previous numerical simulations of unbarred,…

Astrophysics of Galaxies · Physics 2015-10-28 Junichi Baba

We use a high resolution cosmological zoom simulation of a Milky Way-sized halo to study the observable features in velocity and metallicity space associated with the dynamical influence of spiral arms. For the first time, we demonstrate…